Support synonyms for id and translation about go-i18n

[nicksnyder]

Thanks for taking the time to suggest this. poeditor looks like a cool service and I am kind surprised that their format is so similar.

I would rather not introduce complexity into go-i18n as a result of a specific service because then people will ask to support other services. If there were a standard JSON format, I would just support that (but there isn't to my knowledge).

I think the solution here (and for any other service) to either
(1) write a script that marshals go-i18n's format to your desired format, or vice versa, or
(2) write code to read your own format and add the translations directly to the bundle with AddTranslation at runtime.

If poeditor is/becomes the de facto tool for Go projects such that its format becomes the de facto standard, then I am open to revisiting this.

[Noki]

Ok. I already expected this answer. There are so many services that help with translations so I don't expect any of those to become a de facto standard any time soon. ;-)

We just came up with the following simple solution:

1. read the files exported from poeditor
2. replace the keys
3. pass the result to ParseTranslationFileBytes

You should consider pointing out out the ideas of using AddTranslation or ParseTranslationFileBytes to import translations from different formats in the readme.

Best regards
Tobias